U.S. Pat. No. 1,308,503 Martire (1919) at page 1 lines 10 through 18, discloses a switch for acutuating one or more internal combustion engines by means of either or both of two ignition magnetos, the starting of one or more of the engines being eventually effected by a single ignition magneto, and each engine and each magneto being independently operated. The switch does not provide for combining the outputs of the two magnetos.
U.S. Pat. No. 2,015,091 Spohn (1935) discloses at claim 7 a two-spark ignition magneto for internal combustion motors. The magneto has a rotor and a separate stator for each of the two sparks. The rotor has a rotatable bearing-engaging central supporting structure having a series of permanent magnets spaced about the axis of rotation of the rotatable structure. Each stator comprises and a laminated core located adjacent the path of rotation of the magnets. The outputs of the two magnetos are not combined nor is their any suggestion that the two magnetos fire simultaneously. At page 2, lines 64 to page 3 line 2 it is stated "By reason of the fact that there are an odd number of magnets in the illustrated construction and that each set of spark coils cooperates only with a single magnet at a time to produce a spark, the two sets of spark coils will not be symmetrically arranged with respect to the rotor. In the illustrative embodiment of the invention the two coil sets are shown as so arranged with respect to each other that when in inductive relation to two of the magnets of the rotor there will be three magnets between the two coil sets on one side of the magneto and four magnets between the two coil sets on the other side of the magneto." It appears that one magneto supplies a retarded spark for starting an engine and a second magneto supplies an advanced spark for running the engine (see p.2, lines 22-25). The Spohn type magneto is also disclosed in U.S. Pat. No. 2,286,232 of Scott (1942).
U.S. Pat. No. 3,630,185 Wesemeyer et al (1971) discloses an electronic ignition system wherein two electrically different windings are successively influenced by a magnetic flux and generate different successive voltage pulses, of which the first generated has a lower peak value. The pulses are transmitted to the control electrode of an electronic switch which controls an ignition coil and a spark plug. At low starting speeds, the first voltage pulses are below the threshold voltage of the switch so that the spark is caused later by the second voltage pulse. At the high-normal speed of the combustion engine, the first voltage pulse exceeds the threshold voltage, and the spark is earlier produced.
U.S. Pat. No. 864,621 Haubner et al (1975) discloses an additional winding on the magneto of a magneto ignition system to provide base current over a capacitor-diode network and a current limiting resistor to the base of the ignition transistor to assure that the transistor will be switched and held conducting during positive half waves of the magneto output up to the moment of ignition when a control circuit blocks the ignition transistor. The control winding may be on a magneto armature that serves both to feed the ignition control circuit and to operate as a spark coil, or it may be on an entirely separate armature, or on the lighting system armature of the magneto. Instead of such a control winding, a transformer may be provided in the primary circuit to develop the control voltage.
U.S. Pat. No. 3,963,015 Haubner et al (1976) discloses an ignition system in which the spark coil is wound right on the magneto armature and the spark is produced by electronic interruption of a short circuit across the primary winding, the first of a succession of rectified half waves applied to the electronic circuit unit has its amplitude reduced either by insertion of a circuit component in one half wave path of the rectifier to provide damping, or by the configuration of the armature core, or both. The magneto rotor has a U-shaped permanent magnet, the pole faces on the end of the legs of which are rotated past opposed pose faces of the armature core, which has the desired effect if the latter is of asymmetric U-shape or of symmetrical E-shape.
U.S. Pat. No. 3,974,816 Henderson et al (1976) discloses an electronic ignition control system including one coil assembly having a high number of turns to charge the associated capacitors to a desired level when the speed of the engine is low, and another coil assembly having a low number of turns to charge the capacitors to a desired level when the speed of the engine is high to thereby provide energy at a suitable level to fire the associated spark plugs. Separate capacitors are utilized and each capacitor is isolated from the other capacitor in its charging and discharging action and switching devices are connected separately to each capacitor. Thus, if one capacitor or one of the switching devices shorts, those cylinders associated with the shorted capacitor or switching device will ceases functioning; however, the engine will continue to operate on those cylinders not associated with the shorted capacitor or switching device.
U.S. Pat. No. 4,911,126 Notaras (1990) discloses a multiple spark transistor ignition circuit which is able to provide negligible retardation of ignition time, and/or prevent ignition with reverse rotation and/or provide an additional advanced spark and/or govern maximum engine speed and/or progressively advance moment of ignition with increasing engine speed. The basic circuit comprises an ignition circuit with a diode interposed between the primary winding and the remainder of the circuit. Circuits having a single primary winding and dual remainders or dual primary winding and single remainders are also disclosed. A governor circuit having a control transistor, a further potential divider and a control capacitor, is also disclosed.
U.S. Pat. No. 5,544,633 Mottier (1996) discloses an ignition system for an internal combustion engine that operates in two modes. In a first mode, the timing of the spark event is under electronic control. In a second mode, the timing of the spark event is fixed and synchronized to the mechanical rotation of the crankshaft of the engine. Under normal operating conditions, the timing of the spark event is electronically controlled. If the electrical system of the engine malfunctions, the ignition system defaults to the second mode in which ignition timing is mechanically controlled. The above ignition system replaces the redundant magneto ignition systems historically used on aircraft engines.
The inventor, French Grimes, is an expert in the magneto art. He has a business of modifying magnetos for race car drivers. One of the modifications that he has made, and which has been successful for more than one year prior to the filing of the parent application, Ser. No. 08,796,413 has been the replacement of the primary and secondary windings in a magneto with a single primary winding. The output of the magneto is then fed to a high voltage transformer controlled by a set of points to provide ignition.